Article and method for manufacturing same

ABSTRACT

An article includes a substrate; and a color layer deposited on the substrate, wherein the color layer is a chromium oxide-carbon layer; the color layer has an L* value between about 28 to about 32, an a* value between about −1 to about 1, and a b* value between about −1 to about 1 in the CIE L*a*b* color space.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related to co-pending U.S. patentapplications (Attorney Docket No. US34923, US34937, US34942), entitled“ARTICLE AND METHOD FOR MANUFACTURING SAME”, by Zhang et al. Theseapplications have the same assignee as the present application and havebeen concurrently filed herewith. The above-identified applications areincorporated herein by reference.

BACKGROUND

1. Technical Field

The exemplary disclosure generally relates to articles and methods formanufacturing the articles.

2. Description of Related Art

Vacuum deposition is used to form a thin film or coating on housings ofportable electronic devices, to improve abrasion resistance. However,typical vacuum deposition can not deposit absolute black coatings on thehousing.

Therefore, there is room for improvement within the art.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the embodiments can be better understood with referenceto the following drawings. The components in the drawings are notnecessarily drawn to scale, the emphasis instead being placed uponclearly illustrating the principles of the exemplary embodiment of anarticle and method for manufacturing the article. Moreover, in thedrawings like reference numerals designate corresponding partsthroughout the several views. Wherever possible, the same referencenumbers are used throughout the drawings to refer to the same or likeelements of an embodiment.

FIG. 1 illustrates a cross-sectional view of an exemplary embodiment ofan article.

FIG. 2 is a schematic view of a magnetron sputtering coating machine formanufacturing the article in FIG. 1.

DETAILED DESCRIPTION

Referring to FIG. 1, an exemplary embodiment of an article 10manufactured, by a coating process, such as by vacuum deposition, andincludes a substrate 11, a bonding layer 13 deposited on the substrate11 and a color layer 15 deposited on the bonding layer 13 opposite tothe substrate 11. The article 10 may be a housing of an electronicdevice. The substrate 11 may be made of metal, glass, plastic orceramic.

The bonding layer 13 is formed between the substrate 11 and the colorlayer 15 for improving the binding force between the substrate 11 andthe color layer 15. The bonding layer 13 may be made of chromium. Thebonding layer 13 has a thickness ranging from about 0.01 micrometers toabout 0.1 micrometers, and in this exemplary embodiment has a thicknessof about 0.05 micrometers. The bonding layer 13 in this exemplaryembodiment has a color that does not affect the color of the color layer15, such as silver, white, or gray.

The color layer 15 is a chromium oxide-carbon layer. The color layer 15has an L* value between about 28 to about 32, an a* value between about−1 to about 1, and a b* value between about −1 to about 1 in the CIEL*a*b* (CIE LAB) color space, so the color layer 15 is absolute black.The color layer 15 has a thickness ranging from about 0.3 micrometers toabout 1 micrometers.

A method for manufacturing the article 10 manufactured by vacuumdeposition may include at least the following steps.

A substrate 11 is provided. The substrate 11 may be made of metal,glass, plastic or ceramic.

The substrate 11 is pretreated. For example, the substrate 11 may bewashed with a solution (e.g., alcohol or acetone) in an ultrasoniccleaner, to remove, e.g., grease, dirt, and/or impurities. The substrate11 is then dried. The substrate 11 may also be cleaned using argonplasma cleaning. The substrate 11 is retained on a rotating bracket 50in a vacuum chamber 60 of a magnetron sputtering coating machine 100.The vacuum level of the vacuum chamber 60 is adjusted to 8.0×10−3 Pa.Pure argon is fed into the vacuum chamber 60 at a flux of about 300Standard Cubic Centimeters per Minute (sccm) to 600 sccm from a gasinlet 90. A bias voltage is applied to the substrate 11 in a range from−300 to −800 volts for about 5 to about 10 min. The substrate 11 maythen be washed by argon plasma, to further remove any contaminants.Thus, the binding force between the substrate 11 and the color layer 15is enhanced.

The bonding layer 13 is deposited on the substrate 11 by magnetronsputtering. The temperature in the vacuum chamber 60 is adjusted to bein a range from 50 degrees Celsius (° C.) to 180° C., i.e., the reactiontemperature is about 50° C. to about 180° C.; argon is fed into thevacuum chamber 60 at a flux from about 10 sccm to about 200 sccm fromthe gas inlet 90. The substrate 11 is rotated in a range from 1revolution per minute (rpm) to 4 rpm. A chromium target 70 in the vacuumchamber 60 is evaporated at a power from about 5 kW to about 11 kW and abias voltage is applied to the substrate 11 in a range from about −50 toabout −200 volts for about 3 min to about 10 min, to deposit the bondinglayer 13 on the substrate 11.

The color layer 15 is deposited on the bonding layer 13 by magnetronsputtering. The temperature in the vacuum chamber 60 is kept betweenabout 50° C. to about 180° C., i.e., the reaction temperature is about50° C. to about 180° C. Argon is continuously fed into the vacuumchamber 60 at a flux from about 10 sccm to about 200 sccm from the gasinlet 90. Oxygen is fed into the vacuum at a flux from 10 sccm to 50sccm from the gas inlet 90, i.e, the reaction gas for depositing thecolor layer 15 is oxygen. The substrate 11 is rotated in a range fromabout 1 rpm to about 4 rpm. A chromium carbon alloy target 80 in thevacuum chamber 60 is evaporated at a power from about 5 kW to about 11kW. A bias voltage is applied to the substrate 11 is in a range fromabout −50 volts to about −200 volts for about 10 min to about 60 min, todeposit the color layer 15 on the bonding layer 13. The chromium carbonalloy target contains atomic chromium in a range from about 50 to about80 wt %, and in this exemplary embodiment is about 70 wt %.

The color layer 15 is absolute black which has an L* value between about28 to about 32, an a* value between about −1 to about 1, and a b* valuebetween about −1 to about 1 in the CIE L*a*b* (CIE LAB) color space.

In this exemplary embodiment, only one chromium carbon alloy target 80is evaporated to deposit the color layer 15, rather than evaporating twoseparate targets, such as a separate chromium target and a separatecarbon target. So the chromium atom and the carbon atom can besimultaneously deposited on the substrate 11 when the chromium carbonalloy target 80 is evaporated. Additionally, the composition of thecolor layer 15 can be changed by adjusting the flux of the reaction gas,i.e., adjusting the flux of oxygen, to ensure the color of the colorlayer 15 having an L* value between about 28 to about 32, an a* valuebetween about −1 to about 1, and a b* value between about −1 to about 1in the CIE L*a*b* (CIE LAB) color space, thereby an absolute blackcolored article 10 is produced. Furthermore, only evaporating onechromium carbon alloy target also can prevent two separate targets frompolluting each other.

It is to be understood, however, that even through numerouscharacteristics and advantages of the exemplary disclosure have been setforth in the foregoing description, together with details of the systemand function of the disclosure, the disclosure is illustrative only, andchanges may be made in detail, especially in matters of shape, size, andarrangement of parts within the principles of the disclosure to the fullextent indicated by the broad general meaning of the terms in which theappended claims are expressed.

What is claimed is:
 1. An article, comprising: a substrate; and a colorlayer deposited on the substrate, wherein the color layer is a chromiumoxide-carbon layer; the color layer has an L* value between about 28 toabout 32, an a* value between about −1 to about 1, and a b* valuebetween about −1 to about 1 in the CIE L*a*b* color space.
 2. Thearticle as claimed in claim 1, wherein the color layer has a thicknessranging from about 0.3 micrometers to about 1 micrometers.
 3. Thearticle as claimed in claim 1, wherein the substrate is made of metal,glass, plastic or ceramic.
 4. The article as claimed in claim 1, furthercomprising a bonding layer formed between the substrate and the colorlayer for improving the binding force between the substrate and thecolor layer.
 5. The article as claimed in claim 4, wherein the bondinglayer is made of chromium.
 6. The article as claimed in claim 5, whereinthe bonding layer has a thickness ranging from about 0.01 micrometers toabout 0.1 micrometers.
 7. A method for manufacturing a articlecomprising steps of: providing a substrate; and depositing a color layeron the substrate by magnetron sputtering, wherein the substrate isretained in a vacuum chamber, the temperature in the vacuum chamber iskept between about 50° C. to about 180° C., argon is fed into the vacuumchamber at a flux from about 10 sccm to about 200 sccm, oxygen is fedinto the vacuum at a flux from 10 sccm to 50 sccm, a chromium carbonalloy target in the vacuum chamber is evaporated at a power from about 5kW to about 11 kW; a bias voltage is applied to the substrate is in arange from about −50 volts to about −200 volts for about 10 min to about60 min, to deposit the color layer on the substrate.
 8. The method ofclaim 7, wherein the chromium atomic carbon alloy target contains atomicchromium in a range from about 50 to about 80 wt %.
 9. The method ofclaim 7, wherein the atomic chromium content in chromium carbon alloytarget is about 70 wt %.
 10. The method of claim 7, wherein the colorlayer has an L* value between about 28 to about 32, an a* value betweenabout −1 to about 1, and a b* value between about −1 to about 1 in theCIE L*a*b* color space.
 11. The method of claim 7, wherein the colorlayer is a chromium oxide-carbon layer.
 12. The method of claim 7,wherein further including a step of depositing a bonding layer on thesubstrate by magnetron sputtering before depositing the color layer onthe substrate, wherein during depositing the bonding layer, thetemperature in the vacuum chamber is adjusted in a range from 50° C. to180° C., argon is fed into the vacuum chamber at a flux from about 10sccm to about 200 sccm, a chromium target in the vacuum chamber isevaporated at a power from about 5 kW to about 11 kW and a bias voltageis applied to the substrate in a range from about −50 volts to about−200 volts for about 3 min to about 10 min, to deposit the bonding layeron the substrate.